Obtain the population standard deviation, σ, for the given data. Assume that the data represent population data. Round your final answer to one more decimal place than that used for the observations.
The number of years of teaching experience is given below for 12 high-school teachers.
◦ 64.4 yr
◦ 10.2 yr
◦ 8.4 yr
◦ 8.0 yr